アブストラクト(15巻1号:The Bulletin of Kanagawa Dental College)

The Bulletin of Kanagawa Dental College

English

Title : A Case of Impacted Deciduous Second Molar Caused by Anomalies in the Position of the Tooth Germ
Subtitle : CASE REPORT
Authors : Sumio Kumasaka, Saburo Hamada, Kazue Tamura, Hisaaki Shinji, Noboru Uchimura, Morio Higaki
Authors(kana) :
Organization : Department of Pedodontics, Kanagawa Dental College
Journal : The Bulletin of Kanagawa Dental College
Volume : 15
Number : 1
Page : 71-78
Year/Month : 1987 / 3
Article : Report
Publisher : Kanagawa Odontological Society
Abstract : [Abstract] It is believed that tooth impaction is more incidental in deciduous dentition than in a permanent one. It is presumed that tooth impaction results from a systemic or local cause, although the etiologies are still unknown in some cases. However, the impaction of the deciduous teeth caused by the anomalies in the position of permanent teeth from an embryological point of view has been reported in one clinical case only. As the authors encountered a tooth germ above the second deciduous molar, we reported on the clinical findings of the oral cavity and the histological findings of the permanent tooth. A 6-year-old boy was referred to the Pedodontic Clinic at the Kanagawa Dental College Hospital. His mother complained about a delayed eruption of his lower left deciduous second molar. There was nothing unusual about his medical and dental history. The findings from the oral examination revealed a normal condition except for the absence of the lower left deciduous second molar. Radiographic examination revealed that the lower left deciduous second molar was impacted deeply. Above this molar, there was a tooth-like radiopacity. The lower left second bicuspid was not observed on the radiograph. The tooth-like object above the lower left deciduous second molar was extracted and the eruption of the molar has been observed. The extracted object was found to be a small cone-shaped tooth with no root formation. Incremental lines-of-Retzius were observed on the enamel specimen but not the neonatal line. The tooth germ of the lower bicuspid is usually located on the lingual side of the deciduous molar at birth, and subsequently moves to the occlusal side of the deciduous molar. Finally, it is located below the bifurcation of the preceding deciduous molar. For the reasons mentioned, we concluded that the tooth germ of the second bicuspid remained above the deciduous second molar for no apparent reason.
Practice : Dentistry
Keywords : Impacted Deciduous Teeth, Permanent Tooth Germ, Abnormal Position of Dental Germ